Many types of conduit couplings are known in the prior art. One category of conduit couplings includes tube fittings which are used to join a tube or similar conduit and a fitting body.
One variety of tube fittings includes compression fittings. Such fittings involve the use of ferrules, nuts and other component pieces for holding a tube in fluid tight connection with a fitting body. Tube fittings of this variety have drawbacks in that they include several components. Such multiple components add to the cost of the fitting. In addition, the assembly of such fittings requires several steps. The completion of these steps takes time which further adds to the cost of using such connectors. The use of several components and a multi-step assembly process also increases the chance of defects which can result in leakage or other types of failure.
Stake type fittings are also known in the prior art. Such fittings have the advantage of being low in cost and may be assembled at high production rates. Examples of prior art stake type tube fittings are shown in U.S. Pat. Nos. 3,930,928, 3,977,710, 4,200,314, 4,262,942, 4,330,144 and 4,450,618, all of which are owned by the assignee of the present invention.
While the prior art stake type tube fittings perform well, there is always a desire to improve fitting performance, increase production rates and to reduce cost.
Thus, there exists a need for a joint connection for joining a tube and a fitting body that is lower in cost, more resistant to leakage, is more rapidly assembled and has greater resistance to unwanted disassembly due to applied forces.